1. Field of the Invention
This invention relates to a reflective screen, a display device, and a mobile apparatus.
2. Background Art
In a see-through display device, an image is projected on a reflective-transmissive screen to visually present the background of the screen in combination with the projected image. Here, the projected image is reflected from the frontside and backside of the screen having a certain thickness to produce a parallax, which degrades viewability. This problem also occurs in the so-called head-up display (HUD), for example, which can project various traffic information on the windshield of a mobile apparatus, such as a car and an aircraft, to visually present the traffic information simultaneously with the external background image.
JP-A-9-101478(Kokai) discloses a technique based on a hologram combiner that reflects a specific range of wavelengths. However, the reflection wavelength range is wide and decreases the transmittance of white light. Hence, this technique cannot be used for the aforementioned applications.
JP-A-2006-350126(Kokai) discloses a technique related to a guided-mode resonant grating device in which grating members are periodically provided. However, this technique is intended to widen the reflection wavelength range by allowing the gratings to be contiguous to the air, and hence cannot be used for the aforementioned applications, which require a narrow reflection wavelength range.